linux-stable/include/crypto/if_alg.h
Herbert Xu c840ac6af3 crypto: af_alg - Disallow bind/setkey/... after accept(2)
Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded.  An accept(2) call on that
parent socket creates a context which then uses the tfm object.

Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.

This patch guarantees this by using locks and a reference count
on the parent socket.  Any attempt to modify the parent socket will
fail with EBUSY.

Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-18 18:16:09 +08:00

94 lines
2.4 KiB
C

/*
* if_alg: User-space algorithm interface
*
* Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#ifndef _CRYPTO_IF_ALG_H
#define _CRYPTO_IF_ALG_H
#include <linux/compiler.h>
#include <linux/completion.h>
#include <linux/if_alg.h>
#include <linux/scatterlist.h>
#include <linux/types.h>
#include <net/sock.h>
#define ALG_MAX_PAGES 16
struct crypto_async_request;
struct alg_sock {
/* struct sock must be the first member of struct alg_sock */
struct sock sk;
struct sock *parent;
unsigned int refcnt;
const struct af_alg_type *type;
void *private;
};
struct af_alg_completion {
struct completion completion;
int err;
};
struct af_alg_control {
struct af_alg_iv *iv;
int op;
unsigned int aead_assoclen;
};
struct af_alg_type {
void *(*bind)(const char *name, u32 type, u32 mask);
void (*release)(void *private);
int (*setkey)(void *private, const u8 *key, unsigned int keylen);
int (*accept)(void *private, struct sock *sk);
int (*setauthsize)(void *private, unsigned int authsize);
struct proto_ops *ops;
struct module *owner;
char name[14];
};
struct af_alg_sgl {
struct scatterlist sg[ALG_MAX_PAGES + 1];
struct page *pages[ALG_MAX_PAGES];
unsigned int npages;
};
int af_alg_register_type(const struct af_alg_type *type);
int af_alg_unregister_type(const struct af_alg_type *type);
int af_alg_release(struct socket *sock);
void af_alg_release_parent(struct sock *sk);
int af_alg_accept(struct sock *sk, struct socket *newsock);
int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len);
void af_alg_free_sg(struct af_alg_sgl *sgl);
void af_alg_link_sg(struct af_alg_sgl *sgl_prev, struct af_alg_sgl *sgl_new);
int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con);
int af_alg_wait_for_completion(int err, struct af_alg_completion *completion);
void af_alg_complete(struct crypto_async_request *req, int err);
static inline struct alg_sock *alg_sk(struct sock *sk)
{
return (struct alg_sock *)sk;
}
static inline void af_alg_init_completion(struct af_alg_completion *completion)
{
init_completion(&completion->completion);
}
#endif /* _CRYPTO_IF_ALG_H */